>>88213692Freddy would need a reason to go up against the Justice League, or any member of the broader Cape community in DC, and they would likely be drawn in to investigate on a one to one basis...pending the member who logs in that they're investigating a strange series of deaths. So let's do a sampling.
Bruce comes immediately to mind for dealing with Freddy...and he can stay awake long enough to not deal with Freddy directly once he knows what's going on. If they do throw down in the Dreaming, well we've seen Bruce deal with Doctor Destiny in the DCAU rather handedly.
Martian Manhunter in his faking being a human detective days would cheat the hell out of this. As long as he can shift the battle into mental abstractions he can take Freddy...unfortunately his nickname is Martian Jobhunter...
Wonder Woman, I see the power of the Lasso being important here. Moreover, she'd be able to win by cooling it around her own wrists and preventing Freddy from altering the playing field by keeping her mind in a state of her own Truth. That or she gets help from Morpheus and Orpheus...or some Amazon meditative state. It's just a stretch for her to get involved with this mystery without just stumbling into it like an 800lb gorilla.
Superman, Clark Kent is investigating these strange deaths for a Story...and he basically gets fucked up what good. I'm not sure if Freddy is out and out magical enough to heavily damage Clark, or because he expects him to be human he doesn't initially use the force needed kill the Kryptonian because nothing he does to Clark actually can? I dunno.
Midnighter. Freddy has a very very bad day as he finds himself trapped in the fight brain.
Green Lantern. He has the best chance against Jessica until he pushes her rape survivor PTSD too far, and she goes full Willpower on him. The rest of them can take Freddy handedly in a battle of Wills. Just don't know how or why without them just stumbling in.
